Title :
High Q Ni-Zn-Cu Ferrite Inductor for On-Chip Power Module
Author :
Bae, Seok ; Hong, Yang-Ki ; Lee, Jae-Jin ; Jalli, Jeevan ; Abo, Gavin S. ; Lyle, Andrew ; Choi, Byoung C. ; Donohoe, Gregory W.
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Alabama, Tuscaloosa, AL, USA
Abstract :
We fabricated 3 times 3 array of 1 mum thick Ni-Zn-Cu ferrite and air-core planar inductors (5 times 5 mm2 in size; 2.5, 3.5, and 4.5 turns of Cu coil) on 4 inch bare Si wafer and 300 nm thick SiO2/Si wafer, respectively. The ferrite inductor showed higher Q than that of air-core inductor in the range of 7 to 100 MHz. The Q (= 19.5) of 4.5 turn ferrite inductor is 3.3 times higher than that (= 5.9) of 4.5 turn air-core inductor at 10 MHz, and inductance (L) increased by 10%. The Q-factors were found to be about 50 at 2.3 MHz and 20 at 10 MHz, respectively, for the ferrite inductor.
Keywords :
Q-factor; VHF devices; copper compounds; ferrite devices; ferrites; metallic thin films; nickel compounds; silicon; silicon compounds; thin film inductors; wafer-scale integration; zinc compounds; Ni0.5Zn0.3Cu0.2Fe2O4; Q-factors; Si; air-core planar inductors; frequency 7 MHz to 100 MHz; high Q ferrite inductor; inductance; onchip power module; silicon wafer; size 1 mum; size 300 nm; size 4 inch; DC-DC converter; Ni-Zn-Cu ferrite; integrated inductor; on-chip power module;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2009.2023856